Background: Red blood cell distribution width (RDW) is a measure of the variation of red blood cell (RBC) volume that is reported as part of a standard complete blood con(CBC). Studies shows that RDW is a strong independent predictor of morbidity and mortality in patients who have coronary artery disease (CAD). It has been hypothesized that RDW is associated with worse outcomes, as measured by angiographic, procedural and clinical feature, as well as increased in-hospital mortality, in patients who undergo percutaneous coronary intervention (PCI).

Methods: This is a prospective cohort study correlating baseline RDW levels with angiographic, procedural and clinical failure, as well as in-hospital mortality, among patients who undergo PCI. One hundred seventy-one subjects scheduled for elective and emergency PCI were included in the study. Baseline RDW in all patients was determined. Patients were divided into low RDW group (<13.5%) and high RDW group (>13.5%). The subjects were then followed up during their hospital stay, and outcomes as well as in-hospital mortality were determined. Logistic regression was used to correlate RDW with outcomes.

Results: Baseline characteristics show that patients with high RDW were generally older, hypertensive, have lower eGFR, and have a previous history of acute coronary syndrome. There was a strong trend for patients with high RDW to diabetic, have lower EF, and have higher syntax scores. There were significantly more stents deployed in the high RDW group. Patients with high RDW were more likely to have angiographic failure (25 [34.3%] versus 10 [10.2%], p <0.001), likewise procedural and clinical failure (procedural and clinical failure: 29 [39.7%] versus 16 [16.3%], p <0.001 than in the low RDW group. There was no significant difference in occurence of mortality between the two groups (High RDW: 6 [8.2%]; low RDW: 9 [9.2%]; p value = 0.83).

Conclusion: Increased RDW at baseline is associated with more angiographic, procedural and clinical failure rates, but not with in-hospital mortality, among patients who undergo PCI.